media: ov7740: Check for possible NULL return value in control creation

Check that creating the control actually succeeded before accessing it.
A failure would lead to NULL pointer reference. Fix this.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/i2c/ov7740.c b/drivers/media/i2c/ov7740.c
index c9b8bec..cbfa5a3 100644 (file)
--- a/drivers/media/i2c/ov7740.c
+++ b/drivers/media/i2c/ov7740.c
@@ -980,21 +980,26 @@ static int ov7740_init_controls(struct ov7740 *ov7740)
                                        V4L2_CID_HFLIP, 0, 1, 1, 0);
        ov7740->vflip = v4l2_ctrl_new_std(ctrl_hdlr, &ov7740_ctrl_ops,
                                        V4L2_CID_VFLIP, 0, 1, 1, 0);
+
        ov7740->gain = v4l2_ctrl_new_std(ctrl_hdlr, &ov7740_ctrl_ops,
                                       V4L2_CID_GAIN, 0, 1023, 1, 500);
+       if (ov7740->gain)
+               ov7740->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
+
        ov7740->auto_gain = v4l2_ctrl_new_std(ctrl_hdlr, &ov7740_ctrl_ops,
                                            V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
+
        ov7740->exposure = v4l2_ctrl_new_std(ctrl_hdlr, &ov7740_ctrl_ops,
                                           V4L2_CID_EXPOSURE, 0, 65535, 1, 500);
+       if (ov7740->exposure)
+               ov7740->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
+
        ov7740->auto_exposure = v4l2_ctrl_new_std_menu(ctrl_hdlr,
                                        &ov7740_ctrl_ops,
                                        V4L2_CID_EXPOSURE_AUTO,
                                        V4L2_EXPOSURE_MANUAL, 0,
                                        V4L2_EXPOSURE_AUTO);
 
-       ov7740->gain->flags |= V4L2_CTRL_FLAG_VOLATILE;
-       ov7740->exposure->flags |= V4L2_CTRL_FLAG_VOLATILE;
-
        v4l2_ctrl_auto_cluster(3, &ov7740->auto_wb, 0, false);
        v4l2_ctrl_auto_cluster(2, &ov7740->auto_gain, 0, true);
        v4l2_ctrl_auto_cluster(2, &ov7740->auto_exposure,